Problems converting MP4 to AVI

[Missmax]

Hi!
I'm trying to convert an MP4 file to AVI format.
I have tried using ffmpegx but when it converts it the new avi file is only about 60kb in size and not around 350mb as it should be. When I play the avi file in VLC it only lasts about 3 second and i get no video and just a short bleep of sound!
I have looked at the forum on here but need detailed settings for the conversion.

I have also tried 'Handbrake' but it won't even recognise the mp4 file.

Any help would be much appreciated

Thanks for reading

Mac os 10.4 - yes, I know I should upgrade!

[Missmax]

There seems to be a problem with Handbrake. When I open it and select a file it tells me 'Source: No Valid Title Found' and all fields are grayed out. If I click to open 'Source' again then 'cancel' sometimes I can adjust the fields but when I try to open a file to convert it either crashes or I get the 'no valid title found' and all the fields gray out again!

I'm using Handbrake 0.9.1 (this is the most recent version that I can run on mac os 10.4 I think)

[terryj]

What happens when you open the file in QuickTime Pro Player ( pro version, not regular)
and export it out as a DV Stream file?
Then, what happens when you import that DV Stream file into Handbrake, and export it to .avi?

If you were on at least 10.5.3 or higher,
I'd recommend the one stop shop of doing this in VisualHub...but this should work for Tiger....

[pixel zombie]

MPEG Streamclip can do this as can quicktime 7 with the "pro" upgrade(overpriced if you ask me).